Etiology, Pathogenicity. 237 



official reports, 147,285 animals, out of a total number of about 3,000,000 cattle 

 and bufCaloes, had fallen victims to the .disease up to the end of 1906. Ninety-three 

 thousand cases of these occurred in northern Egypt. Arloing estimates the losses 

 at 5,000,000 cattle, and the valuation at 150,000,000 francs. 



Etiology. Nocard, as well as Tartakowsky, proved that the 

 pure tissue fluids of affected animals contain no micro-organ- 

 isms visible with the microscope, and that no organisms could 

 be cultivated with the ordinary methods of procedure. NicoUe 

 & Adil-Bey demonstrated that brain emulsion, intestinal con- 

 tents, cerebro-spinal fluid or peritoneal exudate, when diluted 

 with water pass through the Berkefeld or Chamberland 

 filter; that such filtrates are infectious, and that therefore the 

 contagion belongs to the group of ultramicroscopical micro- 

 organisms. 



Pathogenicity. The contagion is present during the entire 

 disease in all tissue fluids (the nasal secretion of inoculated ani- 

 mals is infective twenty-four hours after inoculation according 

 to Eaupach). Blood taken at the height of the disease and 

 injected subcutaneously into a full grown animal in as small 

 a quantity as 0.001 g. will produce the disease with the same 

 intensity as if for instance 41. of blood had been injected 

 subcutaneously (NieoUe & Adil-Bey). Besides the tissue fluids 

 the virus is present in the different secretions (saliva, nasal dis- 

 charge, urine, feces, bile, tears, vaginal discharge, perspiration), 

 while the infectiousness of the exhaled air is doubtful. Infec- 

 tion with such substances is readily accomplished by subcutane- 

 ous injections or by feeding, while by intravenous injections in- 

 fection results only exceptionally (Kolle). Eepeated passage 

 of the virus through the bodies of cattle does not modify its 

 virulence (Nicolle & Adil-Bey) ; on the other hand when passed 

 through the bodies of sheep and goats it becomes attenuated 

 (Gralambos, Koch). 



Besides cattle and buffaloes, sheep (Galambos) and goats 

 (Woronzow & Eckert) as well as camels (Tartakowsky) may be 

 infected by subcutaneous injections, while infection is less cer- 

 tainly transmitted by feeding infectious material. 



The question whether hogs are also susceptible to the virus of 

 rinderpest has not yet been positively established. While Carre & 

 Fraimbault succeeded in infecting these animals with subcutaneous 

 injections of virulent blood, and Penning obtained positive results on 

 wild hogs, and later reinfected calves from them, Theiler failed in 

 all attempts to produce the disease in hogs in a similar manner. 



Tenacity. Blood or other infectious fluids, sealed in a glass tube, remain 

 virulent for several months (Semmer) ; the same applies to spleen tissue when kept 

 in a dark place. Distilled water mixed with blood loses its virulence within 4 to 5 

 days (Nencki), and if mixed with glycerin inside of 8 days (Edington) ; blood 

 mixed with an equal quantity of bile becomes avirulent in two hours (Lingard), 

 According to older observations (Haubner, Dieckerhoff) the virus remains virulent 

 on hay kept in the stable, or in the hay loft for 3 to 4 months (?), but when exposed 

 to the sunlight it is destroyed in two days. When dried on wool out of doors 

 it becomes avirulent in three days (Woronzow & Eckert). Hides salted for two 



